In a previous publication [1]} we have investigated the \(\Delta \phi _{12}\)  correlation in high-\(p_{\rm T}\)  dijet events by applying
TMD PDFs and parton shower together with NLO calculations of the hard scattering process. The application of TMD PDFs allows a direct investigation of initial state parton radiation (an overview on TMD PDFs is given in Ref. [2]}). While hard perturbative higher order radiation leads to a large azimuthal decorrelation (\({\Delta \phi _{12}}\ll \pi \) ), soft multi-gluon emissions, which cannot be described by fixed order calculations, dominate in the region \({\Delta \phi _{12}}\rightarrow \pi \) . The region of \({\Delta \phi _{12}}\rightarrow \pi \)  is of special interest, since so-called factorization - breaking [3]}, [4]}, [5]} effects could become important in the case of colored final states.
Multijet production is believed to be sensitive to such effects,
as well as vector boson + jet production [6]}.
In order to investigate factorization - breaking effects, we propose to compare the theoretical description of the azimuthal correlation \(\Delta \phi _{12}\)  in multijet production with the one in \(\rm {Z} +\) jet production.
